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Top Parts Per Category
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Top Parts Per Category

MediumSQL · PostgreSQL

Problem

Advance Auto Parts wants to identify the strongest-selling automotive parts across store categories. Write a SQL query that calculates total units sold for each part within each store category during the previous complete calendar quarter.

Output

  1. Return one row per part included in the top three for its store category.
  2. Include store_category, part_id, part_name, total_units_sold, and sales_rank.
  3. Rank parts by total units sold in descending order within each category. Break ties by ascending part_id.
  4. Exclude sales outside the previous complete calendar quarter and sales that cannot be matched to a store or part. Preserve NULL store categories as their own category.

Schema

stores
ColumnTypeDescription
store_idPKINTUnique store identifier
store_nameVARCHAR(100)Store name
store_categoryVARCHAR(50)Business category assigned to the store
parts
ColumnTypeDescription
part_idPKINTUnique automotive part identifier
part_nameVARCHAR(150)Automotive part description
sales
ColumnTypeDescription
sale_idPKINTUnique sales record identifier
store_idINTStore associated with the sale
part_idINTPart associated with the sale
sale_dateDATEDate of the sale
quantityINTNumber of units sold
Tablesstorespartssales
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